The proposed research will continue investigation into change in the health of the older population. The primary questions to be addressed remain the same: How has the health of the older population changed over time, how does health change with age among a longitudinal sample of the older population, and what are the causes and correlates of these changes in health over time and among individuals. Earlier years of this project have used data from National Interview Survey (NHIS) from 1969 through 1986 to document trends in health status and differentials in health status. This project proposes incorporating data on functional ability from other nationally representative samples of the older population along with data previously used from the NHIS to determine whether there have been changes in functioning ability between 1962 and 1986 in the non- institutional population of the U.S. Descriptive information on functioning status change and the co-variates of such change will be determined using three waves of the Longitudinal Study of Aging (LSOA). Changes over time in active life expectancy defined in terms of ability to perform personal care, ability to live independently, and ability to function in the world outside the home will be determined. Active life expectancy will be compared from both longitudinal and cross-sectional data for 1984 and 1986 in order to determine the effects of using these different data sources and methods on conclusions about the length of disabled life of the oldest members of our population.